This invention relates to an improved method for the topical administration of systemically or locally active drugs. Methods used in the past for such topical or percutaneous delivery of drugs involved incorporating the drug to be administered into a bandage or patch for application to the skin. These bandages, which are employed for topical and/or transdermal drug delivery, consist of multiple layers including a backing layer and a discrete reservoir layer containing a drug confined within a body which is adapted to release a predetermined flow of drug to the skin or mucosa to which it is applied. A pressure-sensitive adhesive surface adapted for contact with the skin or mucosa is positioned on one surface of the reservoir remote from the backing member and may be part of the layer containing the drug reservoir.
Those methods used in the past provide a method of delivering drug to the surface, treated at a predetermined rate, but do not have any substantial effect on the rate of absorption of drug by the surface being treated. Thus, the rate of adsorption of the drug is entirely dependent on the permeability of surface (skin or mucosa) being treated.